This study seeks to develop a theoretical explanation of the sexual risk behaviors of Latino youth from immigrant families, specifically Mexican American, Cuban American, and Puerto Rican adolescents using a nationally representative data set, Add Health. The findings of this study can improve by helping to identify at risk subpopulations for HIV infection, and second by helping to establish the salient predictors of behaviors for these subpopulations. There are four primary aims of this study. Primary Aims of the Study: 1. Aim 1 will assess the impact of different types of assimilation experiences on the sexual risk behaviors of Latino youth as defined by a newly developed sociological theory Segmented Assimiliation. 2. Aim 2 will evaluate the relationships between ethnicity, race, assimilation experience, and the sexual risk behaviors of Latino youth. 3. Aim 3 will test mediating pathways (i.e. self-efficacy, knowledge) between the different acculturation types identified in Segmented Assimilation theory and the sexual risk behaviors of Latino youth. 4. Aim 4 will document the prevalence rates of sexual risk behaviors across different ethnic, racial, gender, SES, and age groupings and test the tenet of the Segmented Assimilation theory that immigrants are assimilating into different segments of American society. This study will use a combination of statistical methods and models including Iogit model for binary outcomes, the ordered Iogit model for ordinal outcome, the multinomial Iogit model for nominal outcomes, ZINB for count outcomes, and OLS for continuous outcomes. In cases where violations of OLS assumptions do not allow for BLUE a generalized linear model (GLM) will be used instead. The modified Bonferroni procedure will be used to control for experimental error rates across multiple contrasts for variables with more than one degree of freedom.